SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9b3c07d5dd8693612ba35e95c9187a7945321ec31a4e2cfe984ac5115fdf4818' 
  AND token = 'Ll+QwlTw8fVYsbEh9zlV2JDPgFTRaQ6dxueJZgQAxZk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}